What is talus? Talus, or scree, is a steep slope usually found at the base of a mountain. The block size of the talus is strongly influenced by the type of rock forming the cliff face and the rate of erosion; for example, shale or rapidly eroding sandstone forms unstable, small, loose talus. The unstable nature of shale results in uneven slopes and many rock crevices. Other rocky types, such as hard dolostone caprock, produces stable, very large talus that provides habitat for much larger organisms.
There are several hundred occurrences statewide. Some documented occurrences have good viability and several are protected on public land or private conservation land. This community is limited to regions of the state with steep shale bedrock and talus outcrops, and there are several large, high quality examples. The current trend of this community is probably stable for occurrences on public land, or declining slightly elsewhere due to moderate threats that include development, trampling by visitors, and invasive species.
The number and acreage of shale cliff and talus communities in New York have probably declined slightly in recent decades as a result of development, trampling by visitors, and invasive species.
The number and acreage of shale cliff and talus communities in New York have probably declined moderately from historical numbers likely correlated with past development, trampling by visitors, and invasive species.
Shale cliff and talus communities are threatened by development in the surrounding landscape (e.g., residential, agricultural). Other threats include habitat alteration (e.g., roads and parking areas, nearby logging, and mining), and recreational overuse (e.g., trampling by visitors, ATVs, mountain bikes, campgrounds, picnic areas, swimming, rock and ice climbing, trash dumping). Threats to adjacents streams may apply to this community (e.g., alteration to hydrology, pollution, nutrient loading, impoundments and flooding, dredging). Several shale cliff and talus communities are threatened by invasive species, such as purple loosestrife (Lythrum salicaria), reed canary grass (Phalaris arundinacea), spotted starthistle (Centaurea biebersteinii), and colt's foot (Tussilago farfara).
Where practical establish and maintain a natural forested buffer to reduce storm-water, pollution, and nutrient run-off, while simultaneously capturing sediments before they reach the shale cliff and talus community. Avoid habitat alteration along the cliff and surrounding landscape. Restore shale cliff and talus communities that have been affected by unnatural disturbance (e.g., remove obsolete impoundments in order to restore the natural hydrology to adjacent streams if present). Prevent the spread of invasive exotic species into the shale cliff and talus community through appropriate direct management, and by minimizing potential dispersal corridors, such as roads and trails.
A natural (usually forested) buffer around the cliff face will help it maintain the characteristics that make it unique. It may be desirable to close portions of cliffs for various durations in order to protect rare cliff nesting birds and rare plant habitat.
Survey for occurrences statewide to advance documentation and classification of shale cliff and talus communities. Continue searching for large sites in good condition (A- to AB-ranked).
Research composition of shale cliff and talus communities statewide in order to characterize variations. Collect sufficient plot data to support the recognition of several distinct shale cliff and talus community types based on composition, specific geology, and by ecoregion.
This community is scattered throughout upstate New York, north of the North Atlantic Coast Ecoregion, where the bedrock is shale. Shale bedrock is essentially limited to parts of the High Allegheny Plateau, Western Allegheny Plateau, Great Lakes, and Lower New England Ecoregions. In the Great Lakes Ecoregion, this community is concentrated in the western portion, and is suspected to extend northeast primarily to the escarpment of the Tug Hill. Small disjunct occurrences are known from the northern portion of Lake Champlain.
This physically broadly-defined community may be worldwide, where the bedrock is shale. Examples with the greatest biotic affinities to New York occurrences are suspected to span north to southern Canada, west to Michigan, southwest to Ohio and Tennessee, southeast to Virginia, and northeast to eastern New York and Vermont.
A community that occurs on nearly vertical exposures of shale bedrock and includes ledges and small areas of talus. Talus areas are composed of small fragments that are unstable and steeply sloping; the unstable nature of the shale results in uneven slopes and many rock crevices. There is minimal soil development, and vegetation is usually sparse. Different types of shale cliffs may be distinguished based on exposure and moisture.
Characteristic species include blunt-lobed woodsia (Woodsia obtusa), rusty woodsia (W. ilvensis), penstemon (Penstemon hirsutus), herb robert (Geranium robertianum), cyperus (Cyperus filiculmis), little bluestem (Schizachyrium scoparium), panic grass (Panicum linearifolium), Pennsylvania sedge (Carex pensylvanica), golden sedge (C. aurea), ox-tongue (Picris spp.), and eastern red cedar (Juniperus virginiana). Characteristic bryophyte species on calcareous shale and mudstone cliffs can include the mosses Bryum pseudotriquetrum, Campylium chrysophyllum, Encalypta procera, Fissidens bryoides, Gymnostomum aeruginosum, Mnium marginatum, Myurella siberica, and the leafy liverwort Cololejeunea biddlecomiae. A characteristic invertebrate is the silvery blue butterfly (Glaucopsyche lygdamus lygdamus), which feeds on wood-vetch (Vicia caroliniana).
Known examples of this community have been found at elevations between 10 feet and 1,850 feet.
These dramatic shale exposures are stunning year-round.
This New York natural community encompasses all or part of the concept of the following International Vegetation Classification (IVC) natural community associations. These are often described at finer resolution than New York's natural communities. The IVC is developed and maintained by NatureServe.
This New York natural community falls into the following ecological system(s). Ecological systems are often described at a coarser resolution than New York's natural communities and tend to represent clusters of associations found in similar environments. The ecological systems project is developed and maintained by NatureServe.
Quercus rubra (northern red oak)
Acer spicatum (mountain maple)
Fraxinus americana (white ash)
Tsuga canadensis (eastern hemlock)
Ulmus rubra (slippery elm)
Rubus allegheniensis (common blackberry)
Rubus odoratus (purple-flowering raspberry)
Salix eriocephala (heart-leaved willow, Missouri willow)
Parthenocissus quinquefolia (Virginia-creeper)
Aquilegia canadensis (wild columbine, red columbine)
Aralia racemosa (spikenard)
Cinna latifolia (drooping wood-reed)
Cystopteris fragilis (fragile fern)
Danthonia spicata (poverty grass)
Leucanthemum vulgare (ox-eye daisy)
Lycopus uniflorus (northern bugleweed, northern water-horehound)
Poa compressa (flat-stemmed blue grass, Canada blue grass)
Tussilago farfara (colts-foot)
This figure helps visualize the structure and "look" or "feel" of a typical Shale Cliff and Talus Community. Each bar represents the amount of "coverage" for all the species growing at that height. Because layers overlap (shrubs may grow under trees, for example), the shaded regions can add up to more than 100%.
Edinger, G. J., D. J. Evans, S. Gebauer, T. G. Howard, D. M. Hunt, and A. M. Olivero (editors). 2014. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke’s Ecological Communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation, Albany, NY. https://www.nynhp.org/ecological-communities/
Edinger, Gregory J., D.J. Evans, Shane Gebauer, Timothy G. Howard, David M. Hunt, and Adele M. Olivero (editors). 2002. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke's Ecological Communities of New York State. (Draft for review). New York Natural Heritage Program, New York State Department of Environmental Conservation. Albany, NY. 136 pp.
Hotchkiss, Neil. 1932. A botanical survey of the Tug Hill plateau. New York State Museum Bulletin No. 287. Albany, NY.
Larson, D.W., U. Matthes, and P.E. Kelly. 2000. Cliff Ecology: Pattern and Process in Cliff Ecosystems. Cambridge University Press, New York, New York.
New York Natural Heritage Program. 2023. New York Natural Heritage Program Databases. Albany, NY.
New York Natural Heritage Program. No date. Field forms database: Electronic field data storage and access for New York Heritage ecology, botany, and zoology. New York Natural Heritage Program, New York State Department of Environmental Conservation. Albany, NY.
Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.
Van Diver, Bradford B. 1985. Roadside Geology of New York. Mountain Press Publishing Company, Missoula, MT.
This guide was authored by: Aissa Feldmann
Information for this guide was last updated on: May 2, 2019
Please cite this page as:
New York Natural Heritage Program. 2023. Online Conservation Guide for Shale cliff and talus community. Available from: https://guides.nynhp.org/shale-cliff-and-talus-community/. Accessed January 30, 2023.